From the new book, I take it, based on http://mobile.bloomberg.com/news/2011-10-24/bias-blindness-and-how-we-truly-think-part-1-daniel-kahneman The full quote offers an interesting debiasing strategy:

Klein’s proposal, which he calls the “premortem,” is simple: When the organization has almost come to an important decision but hasn’t committed itself, it should gather a group of people knowledgeable about the decision to listen to a brief speech: “Imagine that we are a year into the future. We implemented the plan as it now exists. The outcome has been a disaster. Please take 5 to 10 minutes to write a brief history of that disaster.”

As a team converges on a decision, public doubts about the wisdom of the planned move are gradually suppressed and eventually come to be treated as evidence of flawed loyalty. The suppression of doubt contributes to overconfidence in a group where only supporters of the decision have a voice. The main virtue of the premortem is that it legitimizes doubts.

Furthermore, it encourages even supporters of the decision to search for possible threats not considered earlier. The premortem isn’t a panacea and doesn’t provide complete protection against nasty surprises, but it goes some way toward reducing the damage of plans that are subject to the biases of uncritical optimism.